Thanks for sharing, that's a very interesting page. Gives me ideas for what I might want to do with my X213 some day.
Interesting to note his change of heart on the water heater drain:
"Update: In reality I only ever drained the water heater once per year at the end of the season. Then I had to remove my hose contraption away to get after the tank with my flushing tool. So I scrapped the above hose and drain valve arrangement and went back to the stock nylon plug."